Is a 30M the same in every brand?

No - a 30M isn't identical across brands, because brands use different sizing systems and cup depths. Here's how a standard US 30M translates in the brands we track: ThirdLove 30M, Wacoal 30M, Panache 30J, Bravissimo 30J, Freya 30J, Elomi 30J, Glamorise 30M, b.tempt'd 30M, Fantasie 30J. SHEFIT, Kindred Bravely, ENELL size by their own chart instead of band/cup.

What are the sister sizes for 30M?

30M's sister sizes — same cup volume, different band — are 28N and 32L. Try a sister size if the band feels too tight or loose but the cup still fits.

30M Bras

What is a 30M in other brands?

160 bras tracked in 30M · 3 brands · See all M cup

Brands: Fantasie, Freya, Panache

Your 30M across brands

A 30M isn’t the same in every brand. Here’s how a standard US 30M translates across the brands we track — and how each one runs.

Brand	How it runs	Your 30M →
ThirdLove	cups run generous	30M
Wacoal	true to size	30M
Panache	true to size	30J
Bravissimo	true to size	30J

What is a 30M in other brands? See all 30+ brands →

Editorial buying guide

Read the 30M buying guide

Top picks, sister sizes, and how to spot a good 30M fit.

Read →

Sister sizes

28N 32L What are sister sizes?

Sort

Your 30M across brands

Bette Balcony Bikini Top - Liliflora Print

Envy Full Cup Bra - Honey

Alice Balcony Strapless Bra - Honey

Alice Balcony Strapless Bra - Black

Anya Riva Spot Balcony Tankini Top - Navy/Vanilla

Katherine Nursing Bra - Black

Boundless Non Wired Sports Bra - Black

Boundless Non Wired Sports Bra - Berry/Chalk

Clara Full Cup Bra - Chai

Allure Full Cup Bra - Ivory

Allure Full Cup Bra - Black/Latte

Clara Full Cup Bra - Charc/Black

Clara Full Cup Bra - Honey

Allure Full Cup Bra - Azure Blue

Allure Full Cup Bra - True Red

Allure Full Cup Bra - Honey

Ana Nursing Bra - Vintage

Lauren Plunge Bikini Top - Black

Lauren Plunge Bikini Top - Cobalt

Lauren Plunge Bikini Top - Red

Freedom Non Wired Sports Bra - Black/Chalk

Power Wired Sports Bra - White

Endurance Wired Sports Bra - Black

Power Wired Sports Bra - Latte

Endurance Wired Sports Bra - Dusty Rose

Endurance Wired Sports Bra - Berry/Chalk

Endurance Wired Sports Bra - Sienna Rose

Bette Balcony Bikini Top - Teal Blue

Endurance Wired Sports Bra - Black/Latte

Lara Plunge Swimsuit - Aurora Red

Iris Balcony Tankini Top - Black Gingham

Paloma Balcony Swimsuit - Red Gingham

Paloma Balcony Swimsuit - Black Gingham

Rita Plunge Swimsuit - Black

Monica Balcony Swimsuit - Liliflora Print

Monica Balcony Swimsuit - Teal Blue

Lara Plunge Swimsuit - Aurora Black/White

Rita Plunge Swimsuit - Cobalt

Rita Plunge Swimsuit - Red

Gigi Balcony Swimsuit - Sparkle Teal